Entergy to replace reactor vessel head, steam generators at Arkansas Nuclear One

Aug. 13, 2002 — Entergy is investing in the future of Arkansas with its decision to replace both steam generators and the reactor vessel head for Arkansas Nuclear One’s Unit 1. Replacement work is scheduled for fall 2005 during the unit’s 19th refueling outage.

New steam generators will mean efficiency gains and improved equipment reliability going forward. A new reactor vessel head will resolve Unit 1’s potential susceptibility to the industry’s generic Alloy 600 reliability issues. Alloy 600, a nickel alloy, is a material commonly used on reactor vessel head nozzle penetrations. After years of prolonged exposure to elevated temperatures and pressure, Alloy 600 has shown a potential for cracking. Repairing such cracks can extend the duration of outages.

Steam generators are massive heat exchangers about 75 feet in length weighing over 500 tons located inside the reactor building. They create steam by transferring heat from water heated in the reactor to water in a secondary system. The steam is used to spin the turbine-generator to create electricity just as in fossil-fueled generating plants.

Both ANO Unit 2 steam generators were replaced in 2000. That was the largest project for the site since original construction. Unit 2 was shut down for 85 days to complete the $150 million project. Unit 2’s reactor vessel head was inspected during this spring’s refueling outage, and no evidence of cracking was found.

The estimated cost to build and install Unit 1’s steam generators and vessel head is about $235 million.

ANO is a valuable emission-free generation asset for Entergy. Entergy Arkansas customers benefited from last year’s record-setting production at the site. Record efficiencies at ANO, combined with a general decrease in fuel costs and purchased power, resulted in a nearly 10 percent reduction on typical residential bills this year.

ANO’s increased production is due primarily to improvements in operational efficiency and equipment reliability and less downtime for refueling. With 56 percent of Entergy Arkansas’ power coming from Arkansas Nuclear One last year, the company spent less on more costly non-nuclear fuels and power purchased on the open market.

Unit 1, in commercial operation since 1974, is licensed to operate until 2034. The Nuclear Regulatory Commission renewed its operating license in 2001, adding 20 years to an authorized 40-year initial operating period scheduled to end in 2014.

Entergy, a global energy company headquartered in New Orleans, is the third largest power generator in the nation with more than 30,000 megawatts of generating capacity, nearly $10 billion in revenue and almost 2.6 million customers. Entergy Nuclear, with headquarters in Jackson, Miss., is the second largest and fastest growing operator of nuclear power plants in the nation.

It operates five reactors at four locations in Arkansas, Mississippi and Louisiana under regulatory jurisdictions and five reactors at four sites in Massachusetts, New York and Vermont. Entergy Nuclear is also the nation’s largest provider of license renewal and decommissioning services to the nuclear power industry.

Entergy Nuclear’s on-line address is www.entergy-nuclear.com

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